Walter Minder (August 6, 1905 – April 1, 1992) was a

Swiss Swiss may refer to: * the adjectival form of Switzerland *Swiss people Places * Swiss, Missouri *Swiss, North Carolina * Swiss, West Virginia *Swiss, Wisconsin Other uses * Swiss-system tournament, in various games and sports * Swiss Internation ...

mineralogist Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the proce ...

and

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...

. In 1931, he became professor of radiology at the Institut du Radium at the University of Bern. He together with Alice Leigh-Smith announced the discovery of element 85 (now called

astatine Astatine is a chemical element with the symbol At and atomic number 85. It is the rarest naturally occurring element in the Earth's crust, occurring only as the decay product of various heavier elements. All of astatine's isotopes are short-live ...

) in 1940 and 1942. He proposed the name

helvetium Astatine is a chemical element with the symbol At and atomic number 85. It is the rarest naturally occurring element in the Earth's crust, occurring only as the decay product of various heavier elements. All of astatine's isotopes are short-live ...

in 1940 and

anglohelvetium Astatine is a chemical element with the symbol At and atomic number 85. It is the rarest naturally occurring element in the Earth's crust, occurring only as the decay product of various heavier elements. All of astatine's isotopes are short-live ...

in 1942 for the new element. Later it was proven that in fact he had not discovered element 85. Later he worked on dosimetry and the effects of

ionising radiation Ionizing radiation (or ionising radiation), including nuclear radiation, consists of subatomic particles or electromagnetic waves that have sufficient energy to ionize atoms or molecules by detaching electrons from them. Some particles can t ...

. He was a

pacifist Pacifism is the opposition or resistance to war, militarism (including conscription and mandatory military service) or violence. Pacifists generally reject theories of Just War. The word ''pacifism'' was coined by the French peace campai ...

and regretted that the atomic bomb had been dropped on

Hiroshima is the capital of Hiroshima Prefecture in Japan. , the city had an estimated population of 1,199,391. The gross domestic product (GDP) in Greater Hiroshima, Hiroshima Urban Employment Area, was US$61.3 billion as of 2010. Kazumi Matsui ...

on his 40th birthday. In 1960 he participated in two pacifist demonstrations against the possibility of Switzerland purchasing nuclear weapons. He retired in 1964. He published a book on the history of radioactivity in 1981.

References

1905 births 1992 deaths Swiss chemists {{chemist-stub